1. Field of the Invention
This invention most generally relates to teaching apparatus. More particularly, the invention is directed to a tank which has two, a front and a rear, substantially planar walls at least one of which is transparent a means for holding the front and rear walls in parallel opposed spaced relationship to form the tank cavity and tank volume defined by the planar dimensions of the front and rear walls and the tank cavity width. Along with the front and rear walls there is a means for sealably defining in combination with the planar walls, at least one working cavity having a working cavity volume. Such means for defining the working cavity is deformable and creates when assembled with the two planar walls, the teaching tank. The means for sealably defining the working cavity forms side walls and bottom walls all of which may or may not be transparent. The volume and/or volumes is/are variable and a function of the placement of and the dimensions of the means for sealably defining the tank cavities. Even more particularly, the means for defining the working cavity may be flexible tubing which is sealingly compressed by the weight and resultant pressure on the tubing from any fluid materials, including liquids, which may be introduced into the working cavity or cavities. The length and the diameter of the tubing effectively determines the volume of the working cavity for a given planar wall dimension. There is also provided various devices, such as stands, fastening means, means for changing the degree of transparency of the planar walls toward opacity all of which are provided in order to better facilitate the use and enhance the usefulness of the teaching tank. The invention is also particularly directed to a kit of components including the front and rear walls made preferably of rigid transparent plastic material, a supply of flexible plastic or rubber or synthetic tubing having different outside diameters (OD's) to be made into selected lengths and to be used to create the working cavities, means for holding the front and rear walls in parallel opposed and predetermined spaced relationship to form the tank volume with the width dimension being about equal to or less than the tubing OD, tank support means or stand, an instruction book including experiments that are performable using the teaching tank and experimental components and materials.
2. Description of the Prior Art
Teachers have always been looking for better ways to enhance their science lessons and to make science come alive in their classroom. They would love to find easier ways for students to learn the concepts and processes of science.
In the past, students were asked to view, as well as, perform various experiments in small test tubes or beakers. Students were very limited to what they could actually observe because of the inherent small size of the apparatus being used. To increase the size would require the use of considerably more materials and the risks associated with some of the experiments because of the character of the materials and chemicals would also be increased. Take for example, a beaker that holds 600 ml (milliliters) of a liquid and having a diameter of approximately 11 cm (centimeters) and a height of about 14 cm. If a reaction took place in the middle of the beaker you may not observe what is actually taking place because of the thickness of the liquid from the center to the edge of the glass and the curvature of the container.
Teachers still have a very difficult time trying to perform a classroom demonstration, for all students to view at the same time using test tubes, flasks or beakers because of the small size of those which may be used with reasonable economy. The curvature of the material, the glass and the container's shape often creates visual distortion. What students think they observed did not, in many instances in fact take place.
There is a serious need for a teaching device/apparatus or tank which has low volume (to reduce material usage for the experiment) but a large surface area to permit observation by a number of people and from a reasonable distance. The tank should have a surface configuration which reduces or substantially eliminates the distortion of the light passing through the material from which the container or vessel is made, have a working cavity geometry such that the majority of the volume of material or fluid contained within the working cavity is close to the surface of the material through which observation takes place. It would be a further advantage to have a working cavity in which the volume and the perimeter shape may be changed thereby permitting a plurality of cavities within the vessel enhancing the observation results of experiments in which comparative studies and observations may be or need to be made. The teaching tank should be easy to assemble and disassemble and to thoroughly clean for reuse. The present invention satisfies all of the above needs-simple, low cost, convenient to use, excellent visual clarity and distant observation, low volume and versatility as to types of experiments which can be performed with excellent group observation potential. The very use of the teaching tank creates an educational advantage for the teacher and the student in that teachers are afforded a more exciting and visual way to demonstrate a principle of science and the student observers are provided with the opportunity to observe demonstrations and to safely perform experiments wherein the phenomena taking place is more accurately observed or observable and thus perhaps better understood.
After reviewing patents which were developed in a search, no structure or method for teaching fundamental scientific facts similar to the present invention was found nor was one suggested. None of the prior art know to the inventor hereof satisfies the need to, in a convenient, safe, low-cost, and highly visual manner, to effectively teach by demonstration and by experiments that usually involve the use of liquids and/or other forms of flowable materials many scientific principles especially those involving chemical reactions.
Kees, U.S. Pat. No. 4,968,258, shows a reusable learning device consisting of two superimposed planar surfaces. One of the planar surfaces is made of a transparent material that permits a clear view of a work sheet placed between the two surfaces. Kees makes no mention of the suitability of this device for chemical reactions involving liquids.
Zandler, U.S. Pat. No. Des. D233,238, shows an ornamented chemical demostration apparatus. The apparatus is a box-like structure made from a transparent material that appears to permit a view of any object inserted therein from both the first and second brodad, rectangular sides. The internal configuration of the device is fixed in size and geometry.
Bellis, U.S. Pat. No. Des. 2,611,201, shows a display apparatus and includes superimposed, transparent sheets for viewing the structural relationship between the components of a machine. Sheets of material bearing representations of different parts of the structure are related. Representations on the bottom sheet may be blanked out by inserting an opaque sheet between between the two transparent materials. This device is not intended as a receptacle for fluids.
The U.S. Pat. Nos. 4,746,009 to Liberman and 4,993,953 to Stein are simply further representitive of the state of the art.